Process of drawing cellulose acetate threads



Patented Jan. 3, 1933 UNITED STATES ALFONS .ASGHERL AND WOLFGANG GRUBER,0F BURGEIAUSEN, GERMANY, ASSIGNORS TO DR. ALEXANDER WAGKER GESELLSCHAETFUR ELEKTROCHEMISGHE INDUS- TRIE, OF MUNICH, BAVARIA, GERMANY PROCESS OFDRAWING CELLULOSE ACETATE THREADS No Drawing. Application filed November14, 1931, Serial No. 575,156, and in Germany November 21, 1930.

This invention relates to a process of drawing cellulose acetate threadsand more particularly to a process of drawing cellulose acetate threadsby wet spinning the reaction mixture of the acetylation process.

In wet spinning cellulose acetate, it is customary to prepare an acetonesoluble mass which is precipitated after the acetylation process andthen dissolved in a suitable solvent. Heretofore, the acetylationreaction mixture was not used for spinning directly into a precipitationliquor as the product formed was undesirable because of insufficientlustre and softness.

We have now found that the acetylation reaction mixture can be used inwet spinning if a chlorine derivative of an aliphatic hydrocarbon, whichis insoluble in the precipitate bath, is added to the acetylationreaction mixture, with increased stretching of the thread and withoutthe disadvantage of a white product being formed. This addition can bemade before the acetylation process or after, for example, during thehydration process. The hydration process consists in treatingtheacetylation reaction mixturewith an aqueous means for the purpose ofchanging the cellulose acetate from the chloroform soluble form to theacetone soluble form. According to the condition of the celluloseacetate and the spinning, pure water may be used in the precipitate bathor salts and the like may be added. When the threads begin toprecipitate in a plastic condition, it is possible to draw the same at avelocity of over 100 meters per minute through an opening of one tenth(0.1) mm. forming a single glossy thread of about 0.3 den. and a tensilestrength of at least 200 g. per 100 den.

According to this invention, we prefer to pass the threads first througha warm precipitate bath and then through a cold precipitate bath. It isalso understood that various softening means, such as resins, etc. maybe added to the acetylation liquor.

E mample I 10 parts of cellulose such as linters are acetylated in thepresence of 0.5 to one part sulphuric acid, 25 parts of acetic anhydride10 parts of linters are acetylated as in Example I described. Then 6parts of acetylene dichloride are added and the reaction mixturehydrated in the known way. The mass is neutralized and spun as inExample I. The temperature of the first precipitate bath is between lOand 50 C., and of the second precipitate bath 10 to 20 C.

Example [[1 10 parts of linters are acetylated with one part of aceticacid, 0.5 to one part of sulphuric acid, 15 parts of ethylene chlorideand 25 parts of acetic anhydride. The excess an hydride is removed andthe mass is hydrated and spun as in Example II.

E wample IV 10 parts of linters are acetylated with a softening agentwithout changing the structure of the cellulose. The excess anhydrideand softening agent are removed by centrifugation and the triacetateformed is hydrated in the known manner with 10 parts of methylenechloride, one part of acetic acid and one part of sulphuric acid. Thefurther treatment as in Example I.

We claim as our invention:

1. Process of drawing cellulose acetate threads comprising adding achlorine substituted aliphatic hydrocarbon containing less than threecarbon atoms, which is insoluble in the precipitate bath, to a mixtureof cellulose, sulphuric acid, acetic anhydride, and acetic acid, andacetylating, hydrating and wet spinning the resulting mass in aprecipitate bath.

2. Process of drawing cellulose acetate threads comprising adding achlorine substituted paraflin hydrocarbon containing less than threecarbon atoms, which is insoluble than three carbon. atoms, which'isinsoluble in the precipitate bath, to a mixture of celliilose, sulphuricacid, acetic anhydride, acetic acid andacetylating, hydrating and wetspinning the resulting mass in a precipitate bath.

' 4. Process of drawing cellulose acetate threads comprising adding achlorine substituted 1 aliphatic hydrocarbon containing less than threecarbon atoms, which isinsol'uble in the precipitate bath, to a mixtureof cellulose, sulphuric acid, acetic anhydride, aceticacid, andacetylating, hydrating and wet spinning the resulting mass in a warm andthen in a cold precipitate bath. i

5. Process 7 of drawing cellulose acetate threads comprising adding achlorine substituted paraffin hydrocarbon containing less than threecarbon atoms, which is insoluble in the precipitate bath, to a mixtureof cellulose, sulphuric acid, acetic anhydride, and acetic acid andacetylating, hydrating and wet spinning the resulting mass in a warm andthen in a cold precipitate bath.

6. Process of drawing .cellulose acetate threads comprising adding achlorine substituted olefine hydrocarbon containing less than threecarbon atoms, which is insoluble in the precipitate bath, to a mixtureof cellulose, sulphuric acid, acetic'anhydride, acetic acid andacetylating, hydrating and wet spinning the resulting mass in' a warmand then in a cold precipitate bath.

:threads' comprising adding a chlorine substituted aliphatic hydrocarboncontaining less than three carbon atoms, which is insoluble -in-theprecipitate bath, toa mixture of cellulose, sulphuric acid, aceticanhydride, acetic acid, and 'acetylating, hydrating and wet spinning theresulting mass in a warm precipitate bath of not above C. andthen in acold of not below 10 C. y

8. Process of drawing cellulose acetate threads comprising adding achlorine substituted paraffin hydrocarbon containing less than threecarbon atoms, which is insoluble in the precipitate bath, to a mixtureof cellu lose, sulphuric acid, acetic anhydride and aceticacid, andacetylating, hydrating and wet spinning the resulting mass in a warmprecipitate bath-0t not above 50 C. and then in a cold of not below 10C. s 9. Process of drawing cellulose acetate 10. Process of drawingcellulose acetate threads comprising adding a member selectning theresulting massin'a precipitate bath 7. Process of drawing celluloseacetatethreads comprising adding a chlorine substituted olefinehydrocarbon containing'less than three carbon atoms, which is insolublein the precipitate bath, to a mixture of cellulose, sulphuric acid,acetic 'anhydride, acetic acid and acetylating, hydrating and wetspinning the resulting mass in a Warm precipitate bath of not above50 C.and then. in a 7 cold of not below 10 C. i i '7 ed from the groupconsisting of methylene chloride, ethylene chloride or acetylenedichloride to "a mixture 'ofcellulose, sulphuric acid, acetic anhydride'and'acetic acid,-. and acetylating, hydrating and Wet spinning theresulting mass in a Warm precipitatebath and then in a cold precipitatebath. H 11. Process of drawing cellulose acetate threads comprisingacetylating cellulose, adding a member selected from the groupconsisting o-fmethylene chloride, ethylene chloride or acetylenedichloride to the acety- 'lation reaction mixture and hydrating and wetspinning the resulting mass in a precipitate bath at between 30 to 50(land then in a precipitate bath at between 10 to 20 C, 12. Process ofdrawing cellulose acetate threads, comprising. acetylating cellulosewithout changing its structure, adding a member selected from the groupconsisting of methylene chloride,ethylene chloride, or acetylenedichlorideto the. acetylation reaction mixture and hydratingand wetspinat between 30 to 50 C. and then in a precipitate bath at between 10to 20 C.

13. Process of drawing cellulose acetate threads comprising acetylatinga mixturezof cellulose, sulphuric acid, acetic anhydride, and aceticacid, hydrating the acetylation reaction mixture, adding a memberselected from the group consisting of methylene chloride, ethylenechloride, or acetylene dichloride and wet spinning the resulting massin" a precipitate bath of 30 to 50 C. andthen in a precipitate bath atbetween 10' to 20 C.

14. Process of drawing celluloseacetate threads comprising wet spinningin a precipita'tebath an acetone soluble acetylation. reaction mixturecontaining a chlorine substituted aliphatic hydrocarbon containing lessthan three carbon atoms, which is insoluble in the precipitate bath.

15. Process of drawing cellulose acetate threads comprising wet spinningin "aprocipitate bath ahydrated acetylation reaction 7 mixturecontaining a chlorine substituted aliphatic hydrocarbon containing lessthan three carbon atoms, which is insoluble in the precipitate bath". iI

16. Process of drawing cellulose acetate threads comprising wet spinning'ina precipitate bath a hydrated acetylation reaction -mixturecontaining a chlorine substituted paraflin hydrocarbon containing lessthan three carbon atoms, which is insoluble in the precipitate bath.

17 Process of drawing cellulose acetate threads comprising Wet spinningin a precipitate bath a hydrated acetylation reaction mixture containinga chlorine substituted olefine hydrocarbon containing less than threecarbon atoms, which is insoluble in the precipitate bath.

Signed at Munich, State of Bavaria, Germany, this 2nd day of November A.D. 1931.

ALFONS ASCHERL. v WOLFGANG GRUBER.

